The present invention relates to an improved swash plate compressor. This type of compressor generally includes a cylinder which is formed with a plurality of axial bores. Double acting pistons are slidably disposed in the bores. A swash plate diagonally mounted on a shaft is connected to the pistons in such a manner that rotation of the shaft and swash plate causes reciprocation of the pistons to compressively displace a fluid. Swash plate compressors are often used as refrigerant compressors for automotive air conditioning systems and the like.
In order to lubricate the swash plate, pistons etc. a lubricant chamber or sump is generally provided in the lower portion of the cylinder containing oil in which the swash plate is partially immersed. The swash plate spashes the oil onto the internal components of the compressor to provide lubrication.
However, since a substantial amount of oil must be splashed about for effective lubrication, a problem has existed in providing a lubricant chamber of sufficient volume to contain the required amount of oil.
One expedient has been to provide a large volume lubricant chamber extending downwardly from the body of the cylinder. Whereas this increases the volume of the lubricant chamber to the required size, the protruding lubricant chamber increases the overall size of the compressor and makes mounting difficult.
In consideration of efficient manufacturing and other considerations, it is desirable for the cylinder to a have circular cross section. Although swash plate compressors having lubricant chambers completely contained in the lower portions of circular cylindrical bodies have been manufactured and used, the lubricant oil volume is only marginally sufficient and failure of such compressors under maximum load conditions has occured due to lack of lubrication. The problem is especially critical during start-up of the compressor.
This problem is overcome in the above identified copending patent application by providing cylinder heads at the ends of the cylinder which are formed with chambers which communicate with and constitute extensions of the lubricant chamber in the cylinder.
However, another problem has remained unsolved in the present type of compressor which is caused by the basic operation of the compressor itself. Due to the fact that the pistons are reciprocated in the respective bores, the inlet and outlet pressures of the compressor fluctuate in a pulsating manner. This leads to excessive mechanical stress and generally degraded operation of the other components of the refrigeration system which are connected to the compressor as well as the compressor itself.